1. Field of the Invention
The present invention relates to an electrical circuit for supplying power to electrical components for driving an engine of a straddle-type vehicle. More specifically, the invention relates to a straddle-type vehicle that omits a main switch for connecting the engine-related electrical components and the battery.
2. Description of Related Art
A straddle-type vehicle such as a motorcycle often includes a main switch for turning on and off power supplied to the engine ignition system and the like. In vehicles used for competitions such as off-road races, however, the main switch may be omitted to prevent misoperation and to reduce weight (for example, see JP-A-2005-193703 (pages 5-6 and FIG. 7)). When the main switch is omitted, the rider keeps holding a clutch lever and pushes a start switch to operate a starter motor and start the engine.
In vehicles in which the main switch is omitted, power supplied by a battery is generally not used for electrical components used for engine operation (hereinafter referred to as “engine-related electrical components”), such as an ignition system. The battery is mainly used to provide power to the starter motor. Therefore, it is only necessary for the straddle type vehicle to control the supply and shutoff of power supplied by the battery to the starter motor.
When power is supplied by the battery to engine-related electrical components, such as during an engine start, it must not be supplied for a long time in order to protect the battery if the engine is not in operation.
When a main switch is omitted, the rider has to conduct a special operation such as holding a clutch lever and pushing a start switch. This is a disadvantage for general-purpose use.